[PATCH] ARM: ls1021a: add platform notifier for dma-coherent requirement

Huan Wang alison.wang at freescale.com
Mon Sep 7 02:45:43 PDT 2015


Hi, Shawn,

> On Fri, Aug 07, 2015 at 06:01:59PM +0800, Alison Wang wrote:
> > This patch adds platform notifier for dma-coherent requirement.
> > Structure arm_coherent_dma_ops is used instead of arm_dma_ops.
> >
> > Signed-off-by: Alison Wang <alison.wang at freescale.com>
> > ---
> >  arch/arm/mach-imx/mach-ls1021a.c | 30 ++++++++++++++++++++++++++++++
> >  1 file changed, 30 insertions(+)
> >
> > diff --git a/arch/arm/mach-imx/mach-ls1021a.c
> > b/arch/arm/mach-imx/mach-ls1021a.c
> > index b89c858..6bfc71b 100644
> > --- a/arch/arm/mach-imx/mach-ls1021a.c
> > +++ b/arch/arm/mach-imx/mach-ls1021a.c
> > @@ -7,10 +7,39 @@
> >   * (at your option) any later version.
> >   */
> >
> > +#include <linux/dma-mapping.h>
> > +#include <linux/of_platform.h>
> >  #include <asm/mach/arch.h>
> >
> >  #include "common.h"
> >
> > +static int ls1021a_platform_notifier(struct notifier_block *nb,
> > +				  unsigned long event, void *__dev) {
> > +	struct device *dev = __dev;
> > +
> > +	if (event != BUS_NOTIFY_ADD_DEVICE)
> > +		return NOTIFY_DONE;
> > +
> > +	if (of_device_is_compatible(dev->of_node, "fsl,etsec2"))
> > +		set_dma_ops(dev, &arm_coherent_dma_ops);
> 
> Why cannot you simply add property dma-coherent for etsec2 node in
> device tree?  In that case, of_dma_configure() will just do the job
> from of_platform_device_create_pdata().
[Alison Wang] Yes, you are right. I will change in v2. Thanks.
> 
> Shawn
> 
> > +	else if (of_property_read_bool(dev->of_node, "dma-coherent"))
> > +		set_dma_ops(dev, &arm_coherent_dma_ops);
> > +
> > +	return NOTIFY_OK;
> > +}
> > +
> > +static struct notifier_block ls1021a_platform_nb = {
> > +	.notifier_call = ls1021a_platform_notifier, };
> > +
> > +static void __init ls1021a_init_machine(void) {
> > +	bus_register_notifier(&platform_bus_type, &ls1021a_platform_nb);
> > +
> > +	of_platform_populate(NULL, of_default_bus_match_table, NULL,
> NULL);
> > +}
> > +
> >  static const char * const ls1021a_dt_compat[] __initconst = {
> >  	"fsl,ls1021a",
> >  	NULL,
> > @@ -18,5 +47,6 @@ static const char * const ls1021a_dt_compat[]
> > __initconst = {
> >
> >  DT_MACHINE_START(LS1021A, "Freescale LS1021A")
> >  	.smp		= smp_ops(ls1021a_smp_ops),
> > +	.init_machine   = ls1021a_init_machine,
> >  	.dt_compat	= ls1021a_dt_compat,
> >  MACHINE_END
> > --
> > 2.1.0.27.g96db324
> >



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